Gefitinib Enhances Mitochondrial Biological Functions in NSCLCs with EGFR Mutations at a High Cell Density

Abstract

Background/aim: Gefitinib is a tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR) and has been approved for the treatment of non-small cell lung cancers (NSCLCs) with EGFR mutations. Here we demonstrated that gefitinib induced a significantly enhanced biological activity of succinate-tetrazolium reductase (STR) in mitochondria and mitochondrial membrane potential in HCC827 cells (EGFR mutation NSCLCs, sensitive to gefitinib) at a high cell density.

Materials and methods: We assessed the biological activity (STR, mitochondrial membrane potential, expression level of Bcl-2 family proteins) of gefitinib on NSCLCs at different cell densities.

Results: The 3D cell culture experiments showed the enhanced mitochondrial biological activity in clustered cell culture treated with gefitinib. Interestingly, the expression levels of Bcl-x_L and Bax, were affected by the cellular number and gefitinib treatment. We also found that gefitinib prevented additive anticancer activity in the combinational treatment with doxorubicin, which induces mitochondria-dependent apoptotic cell death.

Conclusion: Our results indicate that gefitinib may work as a mitochondrial protector against combinational treatment with mitochondria-dependent anticancer agents in high-cell-density.

Keywords: EGFR; Gefitinib; anti-cancer activity; mitochondria; non-small cell lung cancer.